The present invention relates to novel compounds spiro[5-isopropylbicyclo[3.1.0]hexane-2,2'-oxiranes], which were found to be useful not only as important intermediates for producing valuable compounds such as trans-sabinene hydrate utilized as an intensifier for spearmint type flavor or peppermint type flavor, but also per se as perfumes or flavors and moreover as constituents of perfume or flavor compositions, and to processes for producing said novel compounds as well as to a process for producing sabinene hydrates therefrom. More particularly, the present invention relates to the novel compound trans-spiro[5-isopropylbicyclo[3.1.0]hexane-2,2'-oxirane]having the formula (1) ##STR1## as well as to another novel compound cis-spiro[5-isopropylbicyclo[3.1.0]hexane-2,2'-oxirane]having the formula (2) ##STR2## , and further to a process for producing these novel compounds from 5-isopropylbicyclo[3.1.0]hexan-2-one and to another process for producing said novel compounds from 3-isopropyl-2-cyclopenten-1-one as well as process for producing trans- and/or cis-sabinene hydrates by reducing said compounds with a reducing agent.
TRANS- AND CIS-Sabinene hydrates have hitherto been attracted an attention for flavor components for dentifrice, foods and drinks etc. In particular, the trans-sabinene hydrate, which is widely contained in essential oils such as peppermint oil and spearmint oil in an amount of about 1% (for example, it is contained in the essential oil Menta piperita L. in an amount of 0.8%) and in some cases even up to about several %, has specifically been noticed as an intensifier for the peppermint type flavor or spearmint type flavor.